Fail categories
Every MOT defect since 20 May 2018 falls into one of four groups. Dangerous and major defects are both fails. Minor defects and advisories are passes, but they still matter when you're buying.
- Dangerous: a fail. Don't drive the car at all.
- Major: a fail. It needs repairing and a retest.
- Minor: a pass, recorded on the MOT.
- Advisory: a pass, a warning to keep an eye on.
You can't drive a car with a dangerous defect. A car with a major defect has failed, so it has no valid MOT. You can only drive it to repairs or to a booked test. Driving without a valid MOT can bring a fine of up to £1,000, but not when you're driving to a booked MOT or to repairs. Lights and electrics are the most common area for fails, at 9.9% of tests. Check the defects on its MOT history before you buy.
Repairs and the retest
A car that fails with a major or dangerous defect needs repairing and a retest before it can pass. Dangerous defects mean you must not drive it at all. If you do have to move it, it can only go to a garage for repairs or to a booked retest.
Go back to the same test centre if you can. A partial retest, covering only the items that failed, is usually only possible there and within the time limit on GOV.UK. Any other centre means a full test, so ask about the fee before you book.
Buying a car that has failed? Check the MOT history for repeat failures, then ask the seller for: - the failure certificate - receipts for every repair - the pass certificate from the retest
Avoiding it next time
Most failures can be caught before you book. The average car fails 28.4% of first MOT tests, and the areas that fail most are lights and electrics, suspension, brakes and tyres. Walk round the car and check:
- All the lights work, including indicators, brake lights and number plate lights
- Tyres have at least 1.6mm of tread across the central three-quarters
- Brake pads are not worn below 1.5mm
- The car doesn't pull to one side or knock over bumps
Advisories are a warning, not a fail. The car passes, but the fault can become a fail at the next test. Check the MOT history to see what advisories the car has had. The most common are tyres worn close to the legal limit, brake discs worn or pitted, tyres cracking or perishing, and brake pads wearing thin. If you're buying, ask the seller what has been done about them.